blob: cee7c6f428f0fa518e80bda281eb92421a5ac295 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Implementation of the diskquota system for the LINUX operating system. QUOTA
3 * is implemented using the BSD system call interface as the means of
4 * communication with the user level. This file contains the generic routines
5 * called by the different filesystems on allocation of an inode or block.
6 * These routines take care of the administration needed to have a consistent
7 * diskquota tracking system. The ideas of both user and group quotas are based
8 * on the Melbourne quota system as used on BSD derived systems. The internal
9 * implementation is based on one of the several variants of the LINUX
10 * inode-subsystem with added complexity of the diskquota system.
11 *
12 * Version: $Id: dquot.c,v 6.3 1996/11/17 18:35:34 mvw Exp mvw $
13 *
14 * Author: Marco van Wieringen <mvw@planets.elm.net>
15 *
16 * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
17 *
18 * Revised list management to avoid races
19 * -- Bill Hawes, <whawes@star.net>, 9/98
20 *
21 * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
22 * As the consequence the locking was moved from dquot_decr_...(),
23 * dquot_incr_...() to calling functions.
24 * invalidate_dquots() now writes modified dquots.
25 * Serialized quota_off() and quota_on() for mount point.
26 * Fixed a few bugs in grow_dquots().
27 * Fixed deadlock in write_dquot() - we no longer account quotas on
28 * quota files
29 * remove_dquot_ref() moved to inode.c - it now traverses through inodes
30 * add_dquot_ref() restarts after blocking
31 * Added check for bogus uid and fixed check for group in quotactl.
32 * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
33 *
34 * Used struct list_head instead of own list struct
35 * Invalidation of referenced dquots is no longer possible
36 * Improved free_dquots list management
37 * Quota and i_blocks are now updated in one place to avoid races
38 * Warnings are now delayed so we won't block in critical section
39 * Write updated not to require dquot lock
40 * Jan Kara, <jack@suse.cz>, 9/2000
41 *
42 * Added dynamic quota structure allocation
43 * Jan Kara <jack@suse.cz> 12/2000
44 *
45 * Rewritten quota interface. Implemented new quota format and
46 * formats registering.
47 * Jan Kara, <jack@suse.cz>, 2001,2002
48 *
49 * New SMP locking.
50 * Jan Kara, <jack@suse.cz>, 10/2002
51 *
52 * Added journalled quota support, fix lock inversion problems
53 * Jan Kara, <jack@suse.cz>, 2003,2004
54 *
55 * (C) Copyright 1994 - 1997 Marco van Wieringen
56 */
57
58#include <linux/errno.h>
59#include <linux/kernel.h>
60#include <linux/fs.h>
61#include <linux/mount.h>
62#include <linux/mm.h>
63#include <linux/time.h>
64#include <linux/types.h>
65#include <linux/string.h>
66#include <linux/fcntl.h>
67#include <linux/stat.h>
68#include <linux/tty.h>
69#include <linux/file.h>
70#include <linux/slab.h>
71#include <linux/sysctl.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070072#include <linux/init.h>
73#include <linux/module.h>
74#include <linux/proc_fs.h>
75#include <linux/security.h>
76#include <linux/kmod.h>
77#include <linux/namei.h>
78#include <linux/buffer_head.h>
Randy Dunlap16f7e0f2006-01-11 12:17:46 -080079#include <linux/capability.h>
Adrian Bunkbe586ba2005-11-07 00:59:35 -080080#include <linux/quotaops.h>
Christoph Hellwigfb58b732007-02-12 00:51:57 -080081#include <linux/writeback.h> /* for inode_lock, oddly enough.. */
Jan Kara8e893462007-10-16 23:29:31 -070082#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
83#include <net/netlink.h>
84#include <net/genetlink.h>
85#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070086
87#include <asm/uaccess.h>
88
89#define __DQUOT_PARANOIA
90
91/*
92 * There are two quota SMP locks. dq_list_lock protects all lists with quotas
93 * and quota formats and also dqstats structure containing statistics about the
94 * lists. dq_data_lock protects data from dq_dqb and also mem_dqinfo structures
95 * and also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
96 * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
97 * in inode_add_bytes() and inode_sub_bytes().
98 *
99 * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock
100 *
101 * Note that some things (eg. sb pointer, type, id) doesn't change during
102 * the life of the dquot structure and so needn't to be protected by a lock
103 *
104 * Any operation working on dquots via inode pointers must hold dqptr_sem. If
105 * operation is just reading pointers from inode (or not using them at all) the
106 * read lock is enough. If pointers are altered function must hold write lock
107 * (these locking rules also apply for S_NOQUOTA flag in the inode - note that
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800108 * for altering the flag i_mutex is also needed). If operation is holding
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 * reference to dquot in other way (e.g. quotactl ops) it must be guarded by
Ingo Molnard3be9152006-03-23 03:00:29 -0800110 * dqonoff_mutex.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 * This locking assures that:
112 * a) update/access to dquot pointers in inode is serialized
113 * b) everyone is guarded against invalidate_dquots()
114 *
Ingo Molnard3be9152006-03-23 03:00:29 -0800115 * Each dquot has its dq_lock mutex. Locked dquots might not be referenced
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 * from inodes (dquot_alloc_space() and such don't check the dq_lock).
117 * Currently dquot is locked only when it is being read to memory (or space for
118 * it is being allocated) on the first dqget() and when it is being released on
119 * the last dqput(). The allocation and release oparations are serialized by
120 * the dq_lock and by checking the use count in dquot_release(). Write
121 * operations on dquots don't hold dq_lock as they copy data under dq_data_lock
122 * spinlock to internal buffers before writing.
123 *
124 * Lock ordering (including related VFS locks) is the following:
Ingo Molnard3be9152006-03-23 03:00:29 -0800125 * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock >
126 * dqio_mutex
127 * i_mutex on quota files is special (it's below dqio_mutex)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 */
129
130static DEFINE_SPINLOCK(dq_list_lock);
131DEFINE_SPINLOCK(dq_data_lock);
132
133static char *quotatypes[] = INITQFNAMES;
134static struct quota_format_type *quota_formats; /* List of registered formats */
135static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
136
137/* SLAB cache for dquot structures */
Christoph Lametere18b8902006-12-06 20:33:20 -0800138static struct kmem_cache *dquot_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139
140int register_quota_format(struct quota_format_type *fmt)
141{
142 spin_lock(&dq_list_lock);
143 fmt->qf_next = quota_formats;
144 quota_formats = fmt;
145 spin_unlock(&dq_list_lock);
146 return 0;
147}
148
149void unregister_quota_format(struct quota_format_type *fmt)
150{
151 struct quota_format_type **actqf;
152
153 spin_lock(&dq_list_lock);
154 for (actqf = &quota_formats; *actqf && *actqf != fmt; actqf = &(*actqf)->qf_next);
155 if (*actqf)
156 *actqf = (*actqf)->qf_next;
157 spin_unlock(&dq_list_lock);
158}
159
160static struct quota_format_type *find_quota_format(int id)
161{
162 struct quota_format_type *actqf;
163
164 spin_lock(&dq_list_lock);
165 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next);
166 if (!actqf || !try_module_get(actqf->qf_owner)) {
167 int qm;
168
169 spin_unlock(&dq_list_lock);
170
171 for (qm = 0; module_names[qm].qm_fmt_id && module_names[qm].qm_fmt_id != id; qm++);
172 if (!module_names[qm].qm_fmt_id || request_module(module_names[qm].qm_mod_name))
173 return NULL;
174
175 spin_lock(&dq_list_lock);
176 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next);
177 if (actqf && !try_module_get(actqf->qf_owner))
178 actqf = NULL;
179 }
180 spin_unlock(&dq_list_lock);
181 return actqf;
182}
183
184static void put_quota_format(struct quota_format_type *fmt)
185{
186 module_put(fmt->qf_owner);
187}
188
189/*
190 * Dquot List Management:
191 * The quota code uses three lists for dquot management: the inuse_list,
192 * free_dquots, and dquot_hash[] array. A single dquot structure may be
193 * on all three lists, depending on its current state.
194 *
195 * All dquots are placed to the end of inuse_list when first created, and this
196 * list is used for invalidate operation, which must look at every dquot.
197 *
198 * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
199 * and this list is searched whenever we need an available dquot. Dquots are
200 * removed from the list as soon as they are used again, and
201 * dqstats.free_dquots gives the number of dquots on the list. When
202 * dquot is invalidated it's completely released from memory.
203 *
204 * Dquots with a specific identity (device, type and id) are placed on
205 * one of the dquot_hash[] hash chains. The provides an efficient search
206 * mechanism to locate a specific dquot.
207 */
208
209static LIST_HEAD(inuse_list);
210static LIST_HEAD(free_dquots);
211static unsigned int dq_hash_bits, dq_hash_mask;
212static struct hlist_head *dquot_hash;
213
214struct dqstats dqstats;
215
216static void dqput(struct dquot *dquot);
217
218static inline unsigned int
219hashfn(const struct super_block *sb, unsigned int id, int type)
220{
221 unsigned long tmp;
222
223 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
224 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
225}
226
227/*
228 * Following list functions expect dq_list_lock to be held
229 */
230static inline void insert_dquot_hash(struct dquot *dquot)
231{
232 struct hlist_head *head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type);
233 hlist_add_head(&dquot->dq_hash, head);
234}
235
236static inline void remove_dquot_hash(struct dquot *dquot)
237{
238 hlist_del_init(&dquot->dq_hash);
239}
240
241static inline struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, unsigned int id, int type)
242{
243 struct hlist_node *node;
244 struct dquot *dquot;
245
246 hlist_for_each (node, dquot_hash+hashent) {
247 dquot = hlist_entry(node, struct dquot, dq_hash);
248 if (dquot->dq_sb == sb && dquot->dq_id == id && dquot->dq_type == type)
249 return dquot;
250 }
251 return NODQUOT;
252}
253
254/* Add a dquot to the tail of the free list */
255static inline void put_dquot_last(struct dquot *dquot)
256{
Akinobu Mita8e130592006-06-26 00:24:37 -0700257 list_add_tail(&dquot->dq_free, &free_dquots);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 dqstats.free_dquots++;
259}
260
261static inline void remove_free_dquot(struct dquot *dquot)
262{
263 if (list_empty(&dquot->dq_free))
264 return;
265 list_del_init(&dquot->dq_free);
266 dqstats.free_dquots--;
267}
268
269static inline void put_inuse(struct dquot *dquot)
270{
271 /* We add to the back of inuse list so we don't have to restart
272 * when traversing this list and we block */
Akinobu Mita8e130592006-06-26 00:24:37 -0700273 list_add_tail(&dquot->dq_inuse, &inuse_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 dqstats.allocated_dquots++;
275}
276
277static inline void remove_inuse(struct dquot *dquot)
278{
279 dqstats.allocated_dquots--;
280 list_del(&dquot->dq_inuse);
281}
282/*
283 * End of list functions needing dq_list_lock
284 */
285
286static void wait_on_dquot(struct dquot *dquot)
287{
Ingo Molnard3be9152006-03-23 03:00:29 -0800288 mutex_lock(&dquot->dq_lock);
289 mutex_unlock(&dquot->dq_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290}
291
292#define mark_dquot_dirty(dquot) ((dquot)->dq_sb->dq_op->mark_dirty(dquot))
293
294int dquot_mark_dquot_dirty(struct dquot *dquot)
295{
296 spin_lock(&dq_list_lock);
297 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags))
298 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
299 info[dquot->dq_type].dqi_dirty_list);
300 spin_unlock(&dq_list_lock);
301 return 0;
302}
303
304/* This function needs dq_list_lock */
305static inline int clear_dquot_dirty(struct dquot *dquot)
306{
307 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags))
308 return 0;
309 list_del_init(&dquot->dq_dirty);
310 return 1;
311}
312
313void mark_info_dirty(struct super_block *sb, int type)
314{
315 set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags);
316}
317EXPORT_SYMBOL(mark_info_dirty);
318
319/*
320 * Read dquot from disk and alloc space for it
321 */
322
323int dquot_acquire(struct dquot *dquot)
324{
325 int ret = 0, ret2 = 0;
326 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
327
Ingo Molnard3be9152006-03-23 03:00:29 -0800328 mutex_lock(&dquot->dq_lock);
329 mutex_lock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 if (!test_bit(DQ_READ_B, &dquot->dq_flags))
331 ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot);
332 if (ret < 0)
333 goto out_iolock;
334 set_bit(DQ_READ_B, &dquot->dq_flags);
335 /* Instantiate dquot if needed */
336 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
337 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
338 /* Write the info if needed */
339 if (info_dirty(&dqopt->info[dquot->dq_type]))
340 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
341 if (ret < 0)
342 goto out_iolock;
343 if (ret2 < 0) {
344 ret = ret2;
345 goto out_iolock;
346 }
347 }
348 set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
349out_iolock:
Ingo Molnard3be9152006-03-23 03:00:29 -0800350 mutex_unlock(&dqopt->dqio_mutex);
351 mutex_unlock(&dquot->dq_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 return ret;
353}
354
355/*
356 * Write dquot to disk
357 */
358int dquot_commit(struct dquot *dquot)
359{
360 int ret = 0, ret2 = 0;
361 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
362
Ingo Molnard3be9152006-03-23 03:00:29 -0800363 mutex_lock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 spin_lock(&dq_list_lock);
365 if (!clear_dquot_dirty(dquot)) {
366 spin_unlock(&dq_list_lock);
367 goto out_sem;
368 }
369 spin_unlock(&dq_list_lock);
370 /* Inactive dquot can be only if there was error during read/init
371 * => we have better not writing it */
372 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
373 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
374 if (info_dirty(&dqopt->info[dquot->dq_type]))
375 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
376 if (ret >= 0)
377 ret = ret2;
378 }
379out_sem:
Ingo Molnard3be9152006-03-23 03:00:29 -0800380 mutex_unlock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 return ret;
382}
383
384/*
385 * Release dquot
386 */
387int dquot_release(struct dquot *dquot)
388{
389 int ret = 0, ret2 = 0;
390 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
391
Ingo Molnard3be9152006-03-23 03:00:29 -0800392 mutex_lock(&dquot->dq_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 /* Check whether we are not racing with some other dqget() */
394 if (atomic_read(&dquot->dq_count) > 1)
395 goto out_dqlock;
Ingo Molnard3be9152006-03-23 03:00:29 -0800396 mutex_lock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 if (dqopt->ops[dquot->dq_type]->release_dqblk) {
398 ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot);
399 /* Write the info */
400 if (info_dirty(&dqopt->info[dquot->dq_type]))
401 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
402 if (ret >= 0)
403 ret = ret2;
404 }
405 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
Ingo Molnard3be9152006-03-23 03:00:29 -0800406 mutex_unlock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407out_dqlock:
Ingo Molnard3be9152006-03-23 03:00:29 -0800408 mutex_unlock(&dquot->dq_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 return ret;
410}
411
412/* Invalidate all dquots on the list. Note that this function is called after
413 * quota is disabled and pointers from inodes removed so there cannot be new
Jan Kara6362e4d2006-03-23 03:00:17 -0800414 * quota users. There can still be some users of quotas due to inodes being
415 * just deleted or pruned by prune_icache() (those are not attached to any
416 * list). We have to wait for such users.
417 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418static void invalidate_dquots(struct super_block *sb, int type)
419{
Domen Puncerc33ed272005-06-25 14:59:36 -0700420 struct dquot *dquot, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421
Jan Kara6362e4d2006-03-23 03:00:17 -0800422restart:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 spin_lock(&dq_list_lock);
Domen Puncerc33ed272005-06-25 14:59:36 -0700424 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 if (dquot->dq_sb != sb)
426 continue;
427 if (dquot->dq_type != type)
428 continue;
Jan Kara6362e4d2006-03-23 03:00:17 -0800429 /* Wait for dquot users */
430 if (atomic_read(&dquot->dq_count)) {
431 DEFINE_WAIT(wait);
432
433 atomic_inc(&dquot->dq_count);
434 prepare_to_wait(&dquot->dq_wait_unused, &wait,
435 TASK_UNINTERRUPTIBLE);
436 spin_unlock(&dq_list_lock);
437 /* Once dqput() wakes us up, we know it's time to free
438 * the dquot.
439 * IMPORTANT: we rely on the fact that there is always
440 * at most one process waiting for dquot to free.
441 * Otherwise dq_count would be > 1 and we would never
442 * wake up.
443 */
444 if (atomic_read(&dquot->dq_count) > 1)
445 schedule();
446 finish_wait(&dquot->dq_wait_unused, &wait);
447 dqput(dquot);
448 /* At this moment dquot() need not exist (it could be
449 * reclaimed by prune_dqcache(). Hence we must
450 * restart. */
451 goto restart;
452 }
453 /*
454 * Quota now has no users and it has been written on last
455 * dqput()
456 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 remove_dquot_hash(dquot);
458 remove_free_dquot(dquot);
459 remove_inuse(dquot);
460 kmem_cache_free(dquot_cachep, dquot);
461 }
462 spin_unlock(&dq_list_lock);
463}
464
465int vfs_quota_sync(struct super_block *sb, int type)
466{
467 struct list_head *dirty;
468 struct dquot *dquot;
469 struct quota_info *dqopt = sb_dqopt(sb);
470 int cnt;
471
Ingo Molnard3be9152006-03-23 03:00:29 -0800472 mutex_lock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
474 if (type != -1 && cnt != type)
475 continue;
476 if (!sb_has_quota_enabled(sb, cnt))
477 continue;
478 spin_lock(&dq_list_lock);
479 dirty = &dqopt->info[cnt].dqi_dirty_list;
480 while (!list_empty(dirty)) {
Pavel Emelianovb5e61812007-05-08 00:30:19 -0700481 dquot = list_first_entry(dirty, struct dquot, dq_dirty);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 /* Dirty and inactive can be only bad dquot... */
483 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
484 clear_dquot_dirty(dquot);
485 continue;
486 }
487 /* Now we have active dquot from which someone is
488 * holding reference so we can safely just increase
489 * use count */
490 atomic_inc(&dquot->dq_count);
491 dqstats.lookups++;
492 spin_unlock(&dq_list_lock);
493 sb->dq_op->write_dquot(dquot);
494 dqput(dquot);
495 spin_lock(&dq_list_lock);
496 }
497 spin_unlock(&dq_list_lock);
498 }
499
500 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
501 if ((cnt == type || type == -1) && sb_has_quota_enabled(sb, cnt)
502 && info_dirty(&dqopt->info[cnt]))
503 sb->dq_op->write_info(sb, cnt);
504 spin_lock(&dq_list_lock);
505 dqstats.syncs++;
506 spin_unlock(&dq_list_lock);
Ingo Molnard3be9152006-03-23 03:00:29 -0800507 mutex_unlock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508
509 return 0;
510}
511
512/* Free unused dquots from cache */
513static void prune_dqcache(int count)
514{
515 struct list_head *head;
516 struct dquot *dquot;
517
518 head = free_dquots.prev;
519 while (head != &free_dquots && count) {
520 dquot = list_entry(head, struct dquot, dq_free);
521 remove_dquot_hash(dquot);
522 remove_free_dquot(dquot);
523 remove_inuse(dquot);
524 kmem_cache_free(dquot_cachep, dquot);
525 count--;
526 head = free_dquots.prev;
527 }
528}
529
530/*
531 * This is called from kswapd when we think we need some
532 * more memory
533 */
534
Al Viro27496a82005-10-21 03:20:48 -0400535static int shrink_dqcache_memory(int nr, gfp_t gfp_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536{
537 if (nr) {
538 spin_lock(&dq_list_lock);
539 prune_dqcache(nr);
540 spin_unlock(&dq_list_lock);
541 }
542 return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure;
543}
544
Rusty Russell8e1f9362007-07-17 04:03:17 -0700545static struct shrinker dqcache_shrinker = {
546 .shrink = shrink_dqcache_memory,
547 .seeks = DEFAULT_SEEKS,
548};
549
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550/*
551 * Put reference to dquot
552 * NOTE: If you change this function please check whether dqput_blocks() works right...
Ingo Molnard3be9152006-03-23 03:00:29 -0800553 * MUST be called with either dqptr_sem or dqonoff_mutex held
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 */
555static void dqput(struct dquot *dquot)
556{
557 if (!dquot)
558 return;
559#ifdef __DQUOT_PARANOIA
560 if (!atomic_read(&dquot->dq_count)) {
561 printk("VFS: dqput: trying to free free dquot\n");
562 printk("VFS: device %s, dquot of %s %d\n",
563 dquot->dq_sb->s_id,
564 quotatypes[dquot->dq_type],
565 dquot->dq_id);
566 BUG();
567 }
568#endif
569
570 spin_lock(&dq_list_lock);
571 dqstats.drops++;
572 spin_unlock(&dq_list_lock);
573we_slept:
574 spin_lock(&dq_list_lock);
575 if (atomic_read(&dquot->dq_count) > 1) {
576 /* We have more than one user... nothing to do */
577 atomic_dec(&dquot->dq_count);
Jan Kara6362e4d2006-03-23 03:00:17 -0800578 /* Releasing dquot during quotaoff phase? */
579 if (!sb_has_quota_enabled(dquot->dq_sb, dquot->dq_type) &&
580 atomic_read(&dquot->dq_count) == 1)
581 wake_up(&dquot->dq_wait_unused);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 spin_unlock(&dq_list_lock);
583 return;
584 }
585 /* Need to release dquot? */
586 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) {
587 spin_unlock(&dq_list_lock);
588 /* Commit dquot before releasing */
589 dquot->dq_sb->dq_op->write_dquot(dquot);
590 goto we_slept;
591 }
592 /* Clear flag in case dquot was inactive (something bad happened) */
593 clear_dquot_dirty(dquot);
594 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
595 spin_unlock(&dq_list_lock);
596 dquot->dq_sb->dq_op->release_dquot(dquot);
597 goto we_slept;
598 }
599 atomic_dec(&dquot->dq_count);
600#ifdef __DQUOT_PARANOIA
601 /* sanity check */
Eric Sesterhenn8abf6a42006-04-02 13:36:13 +0200602 BUG_ON(!list_empty(&dquot->dq_free));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603#endif
604 put_dquot_last(dquot);
605 spin_unlock(&dq_list_lock);
606}
607
608static struct dquot *get_empty_dquot(struct super_block *sb, int type)
609{
610 struct dquot *dquot;
611
Robert P. J. Dayc3762222007-02-10 01:45:03 -0800612 dquot = kmem_cache_zalloc(dquot_cachep, GFP_NOFS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 if(!dquot)
614 return NODQUOT;
615
Ingo Molnard3be9152006-03-23 03:00:29 -0800616 mutex_init(&dquot->dq_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 INIT_LIST_HEAD(&dquot->dq_free);
618 INIT_LIST_HEAD(&dquot->dq_inuse);
619 INIT_HLIST_NODE(&dquot->dq_hash);
620 INIT_LIST_HEAD(&dquot->dq_dirty);
Jan Kara6362e4d2006-03-23 03:00:17 -0800621 init_waitqueue_head(&dquot->dq_wait_unused);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 dquot->dq_sb = sb;
623 dquot->dq_type = type;
624 atomic_set(&dquot->dq_count, 1);
625
626 return dquot;
627}
628
629/*
630 * Get reference to dquot
Ingo Molnard3be9152006-03-23 03:00:29 -0800631 * MUST be called with either dqptr_sem or dqonoff_mutex held
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 */
633static struct dquot *dqget(struct super_block *sb, unsigned int id, int type)
634{
635 unsigned int hashent = hashfn(sb, id, type);
636 struct dquot *dquot, *empty = NODQUOT;
637
638 if (!sb_has_quota_enabled(sb, type))
639 return NODQUOT;
640we_slept:
641 spin_lock(&dq_list_lock);
642 if ((dquot = find_dquot(hashent, sb, id, type)) == NODQUOT) {
643 if (empty == NODQUOT) {
644 spin_unlock(&dq_list_lock);
645 if ((empty = get_empty_dquot(sb, type)) == NODQUOT)
646 schedule(); /* Try to wait for a moment... */
647 goto we_slept;
648 }
649 dquot = empty;
650 dquot->dq_id = id;
651 /* all dquots go on the inuse_list */
652 put_inuse(dquot);
653 /* hash it first so it can be found */
654 insert_dquot_hash(dquot);
655 dqstats.lookups++;
656 spin_unlock(&dq_list_lock);
657 } else {
658 if (!atomic_read(&dquot->dq_count))
659 remove_free_dquot(dquot);
660 atomic_inc(&dquot->dq_count);
661 dqstats.cache_hits++;
662 dqstats.lookups++;
663 spin_unlock(&dq_list_lock);
664 if (empty)
665 kmem_cache_free(dquot_cachep, empty);
666 }
667 /* Wait for dq_lock - after this we know that either dquot_release() is already
668 * finished or it will be canceled due to dq_count > 1 test */
669 wait_on_dquot(dquot);
670 /* Read the dquot and instantiate it (everything done only if needed) */
671 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && sb->dq_op->acquire_dquot(dquot) < 0) {
672 dqput(dquot);
673 return NODQUOT;
674 }
675#ifdef __DQUOT_PARANOIA
Eric Sesterhenn8abf6a42006-04-02 13:36:13 +0200676 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677#endif
678
679 return dquot;
680}
681
682static int dqinit_needed(struct inode *inode, int type)
683{
684 int cnt;
685
686 if (IS_NOQUOTA(inode))
687 return 0;
688 if (type != -1)
689 return inode->i_dquot[type] == NODQUOT;
690 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
691 if (inode->i_dquot[cnt] == NODQUOT)
692 return 1;
693 return 0;
694}
695
Ingo Molnard3be9152006-03-23 03:00:29 -0800696/* This routine is guarded by dqonoff_mutex mutex */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697static void add_dquot_ref(struct super_block *sb, int type)
698{
Christoph Hellwigd003fb72007-02-12 00:51:58 -0800699 struct inode *inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700
701restart:
Christoph Hellwigd003fb72007-02-12 00:51:58 -0800702 spin_lock(&inode_lock);
703 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
704 if (!atomic_read(&inode->i_writecount))
705 continue;
706 if (!dqinit_needed(inode, type))
707 continue;
708 if (inode->i_state & (I_FREEING|I_WILL_FREE))
709 continue;
710
711 __iget(inode);
712 spin_unlock(&inode_lock);
713
714 sb->dq_op->initialize(inode, type);
715 iput(inode);
716 /* As we may have blocked we had better restart... */
717 goto restart;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718 }
Christoph Hellwigd003fb72007-02-12 00:51:58 -0800719 spin_unlock(&inode_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720}
721
722/* Return 0 if dqput() won't block (note that 1 doesn't necessarily mean blocking) */
723static inline int dqput_blocks(struct dquot *dquot)
724{
725 if (atomic_read(&dquot->dq_count) <= 1)
726 return 1;
727 return 0;
728}
729
730/* Remove references to dquots from inode - add dquot to list for freeing if needed */
731/* We can't race with anybody because we hold dqptr_sem for writing... */
Adrian Bunke5f00f42007-05-08 00:27:22 -0700732static int remove_inode_dquot_ref(struct inode *inode, int type,
733 struct list_head *tofree_head)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734{
735 struct dquot *dquot = inode->i_dquot[type];
736
737 inode->i_dquot[type] = NODQUOT;
738 if (dquot != NODQUOT) {
739 if (dqput_blocks(dquot)) {
740#ifdef __DQUOT_PARANOIA
741 if (atomic_read(&dquot->dq_count) != 1)
742 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count));
743#endif
744 spin_lock(&dq_list_lock);
745 list_add(&dquot->dq_free, tofree_head); /* As dquot must have currently users it can't be on the free list... */
746 spin_unlock(&dq_list_lock);
747 return 1;
748 }
749 else
750 dqput(dquot); /* We have guaranteed we won't block */
751 }
752 return 0;
753}
754
755/* Free list of dquots - called from inode.c */
756/* dquots are removed from inodes, no new references can be got so we are the only ones holding reference */
757static void put_dquot_list(struct list_head *tofree_head)
758{
759 struct list_head *act_head;
760 struct dquot *dquot;
761
762 act_head = tofree_head->next;
763 /* So now we have dquots on the list... Just free them */
764 while (act_head != tofree_head) {
765 dquot = list_entry(act_head, struct dquot, dq_free);
766 act_head = act_head->next;
767 list_del_init(&dquot->dq_free); /* Remove dquot from the list so we won't have problems... */
768 dqput(dquot);
769 }
770}
771
Christoph Hellwigfb58b732007-02-12 00:51:57 -0800772static void remove_dquot_ref(struct super_block *sb, int type,
773 struct list_head *tofree_head)
774{
775 struct inode *inode;
776
777 spin_lock(&inode_lock);
778 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
779 if (!IS_NOQUOTA(inode))
780 remove_inode_dquot_ref(inode, type, tofree_head);
781 }
782 spin_unlock(&inode_lock);
783}
784
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785/* Gather all references from inodes and drop them */
786static void drop_dquot_ref(struct super_block *sb, int type)
787{
788 LIST_HEAD(tofree_head);
789
Christoph Hellwigfb58b732007-02-12 00:51:57 -0800790 if (sb->dq_op) {
791 down_write(&sb_dqopt(sb)->dqptr_sem);
792 remove_dquot_ref(sb, type, &tofree_head);
793 up_write(&sb_dqopt(sb)->dqptr_sem);
794 put_dquot_list(&tofree_head);
795 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796}
797
798static inline void dquot_incr_inodes(struct dquot *dquot, unsigned long number)
799{
800 dquot->dq_dqb.dqb_curinodes += number;
801}
802
803static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
804{
805 dquot->dq_dqb.dqb_curspace += number;
806}
807
808static inline void dquot_decr_inodes(struct dquot *dquot, unsigned long number)
809{
810 if (dquot->dq_dqb.dqb_curinodes > number)
811 dquot->dq_dqb.dqb_curinodes -= number;
812 else
813 dquot->dq_dqb.dqb_curinodes = 0;
814 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
815 dquot->dq_dqb.dqb_itime = (time_t) 0;
816 clear_bit(DQ_INODES_B, &dquot->dq_flags);
817}
818
819static inline void dquot_decr_space(struct dquot *dquot, qsize_t number)
820{
821 if (dquot->dq_dqb.dqb_curspace > number)
822 dquot->dq_dqb.dqb_curspace -= number;
823 else
824 dquot->dq_dqb.dqb_curspace = 0;
825 if (toqb(dquot->dq_dqb.dqb_curspace) <= dquot->dq_dqb.dqb_bsoftlimit)
826 dquot->dq_dqb.dqb_btime = (time_t) 0;
827 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
828}
829
Jan Karac5254602007-12-22 14:03:25 -0800830static int warning_issued(struct dquot *dquot, const int warntype)
831{
832 int flag = (warntype == QUOTA_NL_BHARDWARN ||
833 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B :
834 ((warntype == QUOTA_NL_IHARDWARN ||
835 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0);
836
837 if (!flag)
838 return 0;
839 return test_and_set_bit(flag, &dquot->dq_flags);
840}
841
Jan Kara8e893462007-10-16 23:29:31 -0700842#ifdef CONFIG_PRINT_QUOTA_WARNING
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843static int flag_print_warnings = 1;
844
845static inline int need_print_warning(struct dquot *dquot)
846{
847 if (!flag_print_warnings)
848 return 0;
849
850 switch (dquot->dq_type) {
851 case USRQUOTA:
852 return current->fsuid == dquot->dq_id;
853 case GRPQUOTA:
854 return in_group_p(dquot->dq_id);
855 }
856 return 0;
857}
858
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859/* Print warning to user which exceeded quota */
Jan Karac5254602007-12-22 14:03:25 -0800860static void print_warning(struct dquot *dquot, const int warntype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861{
862 char *msg = NULL;
Peter Zijlstra24ec8392006-12-08 02:36:04 -0800863 struct tty_struct *tty;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864
Jan Karac5254602007-12-22 14:03:25 -0800865 if (!need_print_warning(dquot))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866 return;
867
Jan Karab525a7e2006-09-29 02:00:26 -0700868 mutex_lock(&tty_mutex);
Peter Zijlstra24ec8392006-12-08 02:36:04 -0800869 tty = get_current_tty();
870 if (!tty)
Jan Karab525a7e2006-09-29 02:00:26 -0700871 goto out_lock;
Peter Zijlstra24ec8392006-12-08 02:36:04 -0800872 tty_write_message(tty, dquot->dq_sb->s_id);
Jan Kara8e893462007-10-16 23:29:31 -0700873 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN)
Peter Zijlstra24ec8392006-12-08 02:36:04 -0800874 tty_write_message(tty, ": warning, ");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875 else
Peter Zijlstra24ec8392006-12-08 02:36:04 -0800876 tty_write_message(tty, ": write failed, ");
877 tty_write_message(tty, quotatypes[dquot->dq_type]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700878 switch (warntype) {
Jan Kara8e893462007-10-16 23:29:31 -0700879 case QUOTA_NL_IHARDWARN:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880 msg = " file limit reached.\r\n";
881 break;
Jan Kara8e893462007-10-16 23:29:31 -0700882 case QUOTA_NL_ISOFTLONGWARN:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883 msg = " file quota exceeded too long.\r\n";
884 break;
Jan Kara8e893462007-10-16 23:29:31 -0700885 case QUOTA_NL_ISOFTWARN:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886 msg = " file quota exceeded.\r\n";
887 break;
Jan Kara8e893462007-10-16 23:29:31 -0700888 case QUOTA_NL_BHARDWARN:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 msg = " block limit reached.\r\n";
890 break;
Jan Kara8e893462007-10-16 23:29:31 -0700891 case QUOTA_NL_BSOFTLONGWARN:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892 msg = " block quota exceeded too long.\r\n";
893 break;
Jan Kara8e893462007-10-16 23:29:31 -0700894 case QUOTA_NL_BSOFTWARN:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 msg = " block quota exceeded.\r\n";
896 break;
897 }
Peter Zijlstra24ec8392006-12-08 02:36:04 -0800898 tty_write_message(tty, msg);
Jan Karab525a7e2006-09-29 02:00:26 -0700899out_lock:
900 mutex_unlock(&tty_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901}
Jan Kara8e893462007-10-16 23:29:31 -0700902#endif
903
904#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
905
Jan Kara8e893462007-10-16 23:29:31 -0700906/* Netlink family structure for quota */
907static struct genl_family quota_genl_family = {
908 .id = GENL_ID_GENERATE,
909 .hdrsize = 0,
910 .name = "VFS_DQUOT",
911 .version = 1,
912 .maxattr = QUOTA_NL_A_MAX,
913};
914
915/* Send warning to userspace about user which exceeded quota */
916static void send_warning(const struct dquot *dquot, const char warntype)
917{
918 static atomic_t seq;
919 struct sk_buff *skb;
920 void *msg_head;
921 int ret;
Jan Kara22dd4832007-12-22 14:03:25 -0800922 int msg_size = 4 * nla_total_size(sizeof(u32)) +
923 2 * nla_total_size(sizeof(u64));
Jan Kara8e893462007-10-16 23:29:31 -0700924
925 /* We have to allocate using GFP_NOFS as we are called from a
926 * filesystem performing write and thus further recursion into
927 * the fs to free some data could cause deadlocks. */
Jan Kara22dd4832007-12-22 14:03:25 -0800928 skb = genlmsg_new(msg_size, GFP_NOFS);
Jan Kara8e893462007-10-16 23:29:31 -0700929 if (!skb) {
930 printk(KERN_ERR
931 "VFS: Not enough memory to send quota warning.\n");
932 return;
933 }
934 msg_head = genlmsg_put(skb, 0, atomic_add_return(1, &seq),
935 &quota_genl_family, 0, QUOTA_NL_C_WARNING);
936 if (!msg_head) {
937 printk(KERN_ERR
938 "VFS: Cannot store netlink header in quota warning.\n");
939 goto err_out;
940 }
941 ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, dquot->dq_type);
942 if (ret)
943 goto attr_err_out;
944 ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID, dquot->dq_id);
945 if (ret)
946 goto attr_err_out;
947 ret = nla_put_u32(skb, QUOTA_NL_A_WARNING, warntype);
948 if (ret)
949 goto attr_err_out;
950 ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MAJOR,
951 MAJOR(dquot->dq_sb->s_dev));
952 if (ret)
953 goto attr_err_out;
954 ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MINOR,
955 MINOR(dquot->dq_sb->s_dev));
956 if (ret)
957 goto attr_err_out;
958 ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID, current->user->uid);
959 if (ret)
960 goto attr_err_out;
961 genlmsg_end(skb, msg_head);
962
963 ret = genlmsg_multicast(skb, 0, quota_genl_family.id, GFP_NOFS);
964 if (ret < 0 && ret != -ESRCH)
965 printk(KERN_ERR
966 "VFS: Failed to send notification message: %d\n", ret);
967 return;
968attr_err_out:
Jan Kara22dd4832007-12-22 14:03:25 -0800969 printk(KERN_ERR "VFS: Not enough space to compose quota message!\n");
Jan Kara8e893462007-10-16 23:29:31 -0700970err_out:
971 kfree_skb(skb);
972}
973#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974
Jan Kara087ee8d2007-12-17 16:20:26 -0800975static inline void flush_warnings(struct dquot * const *dquots, char *warntype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976{
977 int i;
978
979 for (i = 0; i < MAXQUOTAS; i++)
Jan Karac5254602007-12-22 14:03:25 -0800980 if (dquots[i] != NODQUOT && warntype[i] != QUOTA_NL_NOWARN &&
981 !warning_issued(dquots[i], warntype[i])) {
Jan Kara8e893462007-10-16 23:29:31 -0700982#ifdef CONFIG_PRINT_QUOTA_WARNING
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983 print_warning(dquots[i], warntype[i]);
Jan Kara8e893462007-10-16 23:29:31 -0700984#endif
985#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
986 send_warning(dquots[i], warntype[i]);
987#endif
988 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989}
990
991static inline char ignore_hardlimit(struct dquot *dquot)
992{
993 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
994
995 return capable(CAP_SYS_RESOURCE) &&
996 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || !(info->dqi_flags & V1_DQF_RSQUASH));
997}
998
999/* needs dq_data_lock */
1000static int check_idq(struct dquot *dquot, ulong inodes, char *warntype)
1001{
Jan Kara8e893462007-10-16 23:29:31 -07001002 *warntype = QUOTA_NL_NOWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003 if (inodes <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags))
1004 return QUOTA_OK;
1005
1006 if (dquot->dq_dqb.dqb_ihardlimit &&
1007 (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_ihardlimit &&
1008 !ignore_hardlimit(dquot)) {
Jan Kara8e893462007-10-16 23:29:31 -07001009 *warntype = QUOTA_NL_IHARDWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010 return NO_QUOTA;
1011 }
1012
1013 if (dquot->dq_dqb.dqb_isoftlimit &&
1014 (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit &&
1015 dquot->dq_dqb.dqb_itime && get_seconds() >= dquot->dq_dqb.dqb_itime &&
1016 !ignore_hardlimit(dquot)) {
Jan Kara8e893462007-10-16 23:29:31 -07001017 *warntype = QUOTA_NL_ISOFTLONGWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018 return NO_QUOTA;
1019 }
1020
1021 if (dquot->dq_dqb.dqb_isoftlimit &&
1022 (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit &&
1023 dquot->dq_dqb.dqb_itime == 0) {
Jan Kara8e893462007-10-16 23:29:31 -07001024 *warntype = QUOTA_NL_ISOFTWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001025 dquot->dq_dqb.dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
1026 }
1027
1028 return QUOTA_OK;
1029}
1030
1031/* needs dq_data_lock */
1032static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype)
1033{
Jan Kara8e893462007-10-16 23:29:31 -07001034 *warntype = QUOTA_NL_NOWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035 if (space <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags))
1036 return QUOTA_OK;
1037
1038 if (dquot->dq_dqb.dqb_bhardlimit &&
1039 toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bhardlimit &&
1040 !ignore_hardlimit(dquot)) {
1041 if (!prealloc)
Jan Kara8e893462007-10-16 23:29:31 -07001042 *warntype = QUOTA_NL_BHARDWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043 return NO_QUOTA;
1044 }
1045
1046 if (dquot->dq_dqb.dqb_bsoftlimit &&
1047 toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit &&
1048 dquot->dq_dqb.dqb_btime && get_seconds() >= dquot->dq_dqb.dqb_btime &&
1049 !ignore_hardlimit(dquot)) {
1050 if (!prealloc)
Jan Kara8e893462007-10-16 23:29:31 -07001051 *warntype = QUOTA_NL_BSOFTLONGWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052 return NO_QUOTA;
1053 }
1054
1055 if (dquot->dq_dqb.dqb_bsoftlimit &&
1056 toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit &&
1057 dquot->dq_dqb.dqb_btime == 0) {
1058 if (!prealloc) {
Jan Kara8e893462007-10-16 23:29:31 -07001059 *warntype = QUOTA_NL_BSOFTWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060 dquot->dq_dqb.dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace;
1061 }
1062 else
1063 /*
1064 * We don't allow preallocation to exceed softlimit so exceeding will
1065 * be always printed
1066 */
1067 return NO_QUOTA;
1068 }
1069
1070 return QUOTA_OK;
1071}
1072
1073/*
1074 * Initialize quota pointers in inode
1075 * Transaction must be started at entry
1076 */
1077int dquot_initialize(struct inode *inode, int type)
1078{
1079 unsigned int id = 0;
1080 int cnt, ret = 0;
1081
Ingo Molnard3be9152006-03-23 03:00:29 -08001082 /* First test before acquiring mutex - solves deadlocks when we
1083 * re-enter the quota code and are already holding the mutex */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084 if (IS_NOQUOTA(inode))
1085 return 0;
1086 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1087 /* Having dqptr_sem we know NOQUOTA flags can't be altered... */
1088 if (IS_NOQUOTA(inode))
1089 goto out_err;
1090 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1091 if (type != -1 && cnt != type)
1092 continue;
1093 if (inode->i_dquot[cnt] == NODQUOT) {
1094 switch (cnt) {
1095 case USRQUOTA:
1096 id = inode->i_uid;
1097 break;
1098 case GRPQUOTA:
1099 id = inode->i_gid;
1100 break;
1101 }
1102 inode->i_dquot[cnt] = dqget(inode->i_sb, id, cnt);
1103 }
1104 }
1105out_err:
1106 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1107 return ret;
1108}
1109
1110/*
1111 * Release all quotas referenced by inode
1112 * Transaction must be started at an entry
1113 */
1114int dquot_drop(struct inode *inode)
1115{
1116 int cnt;
1117
1118 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1119 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1120 if (inode->i_dquot[cnt] != NODQUOT) {
1121 dqput(inode->i_dquot[cnt]);
1122 inode->i_dquot[cnt] = NODQUOT;
1123 }
1124 }
1125 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1126 return 0;
1127}
1128
1129/*
1130 * Following four functions update i_blocks+i_bytes fields and
1131 * quota information (together with appropriate checks)
1132 * NOTE: We absolutely rely on the fact that caller dirties
1133 * the inode (usually macros in quotaops.h care about this) and
1134 * holds a handle for the current transaction so that dquot write and
1135 * inode write go into the same transaction.
1136 */
1137
1138/*
1139 * This operation can block, but only after everything is updated
1140 */
1141int dquot_alloc_space(struct inode *inode, qsize_t number, int warn)
1142{
1143 int cnt, ret = NO_QUOTA;
1144 char warntype[MAXQUOTAS];
1145
Ingo Molnard3be9152006-03-23 03:00:29 -08001146 /* First test before acquiring mutex - solves deadlocks when we
1147 * re-enter the quota code and are already holding the mutex */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148 if (IS_NOQUOTA(inode)) {
1149out_add:
1150 inode_add_bytes(inode, number);
1151 return QUOTA_OK;
1152 }
1153 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
Jan Kara8e893462007-10-16 23:29:31 -07001154 warntype[cnt] = QUOTA_NL_NOWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155
1156 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1157 if (IS_NOQUOTA(inode)) { /* Now we can do reliable test... */
1158 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1159 goto out_add;
1160 }
1161 spin_lock(&dq_data_lock);
1162 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1163 if (inode->i_dquot[cnt] == NODQUOT)
1164 continue;
1165 if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt) == NO_QUOTA)
1166 goto warn_put_all;
1167 }
1168 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1169 if (inode->i_dquot[cnt] == NODQUOT)
1170 continue;
1171 dquot_incr_space(inode->i_dquot[cnt], number);
1172 }
1173 inode_add_bytes(inode, number);
1174 ret = QUOTA_OK;
1175warn_put_all:
1176 spin_unlock(&dq_data_lock);
1177 if (ret == QUOTA_OK)
1178 /* Dirtify all the dquots - this can block when journalling */
1179 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1180 if (inode->i_dquot[cnt])
1181 mark_dquot_dirty(inode->i_dquot[cnt]);
1182 flush_warnings(inode->i_dquot, warntype);
1183 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1184 return ret;
1185}
1186
1187/*
1188 * This operation can block, but only after everything is updated
1189 */
1190int dquot_alloc_inode(const struct inode *inode, unsigned long number)
1191{
1192 int cnt, ret = NO_QUOTA;
1193 char warntype[MAXQUOTAS];
1194
Ingo Molnard3be9152006-03-23 03:00:29 -08001195 /* First test before acquiring mutex - solves deadlocks when we
1196 * re-enter the quota code and are already holding the mutex */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001197 if (IS_NOQUOTA(inode))
1198 return QUOTA_OK;
1199 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
Jan Kara8e893462007-10-16 23:29:31 -07001200 warntype[cnt] = QUOTA_NL_NOWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001201 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1202 if (IS_NOQUOTA(inode)) {
1203 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1204 return QUOTA_OK;
1205 }
1206 spin_lock(&dq_data_lock);
1207 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1208 if (inode->i_dquot[cnt] == NODQUOT)
1209 continue;
1210 if (check_idq(inode->i_dquot[cnt], number, warntype+cnt) == NO_QUOTA)
1211 goto warn_put_all;
1212 }
1213
1214 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1215 if (inode->i_dquot[cnt] == NODQUOT)
1216 continue;
1217 dquot_incr_inodes(inode->i_dquot[cnt], number);
1218 }
1219 ret = QUOTA_OK;
1220warn_put_all:
1221 spin_unlock(&dq_data_lock);
1222 if (ret == QUOTA_OK)
1223 /* Dirtify all the dquots - this can block when journalling */
1224 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1225 if (inode->i_dquot[cnt])
1226 mark_dquot_dirty(inode->i_dquot[cnt]);
Jan Kara087ee8d2007-12-17 16:20:26 -08001227 flush_warnings(inode->i_dquot, warntype);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1229 return ret;
1230}
1231
1232/*
1233 * This operation can block, but only after everything is updated
1234 */
1235int dquot_free_space(struct inode *inode, qsize_t number)
1236{
1237 unsigned int cnt;
1238
Ingo Molnard3be9152006-03-23 03:00:29 -08001239 /* First test before acquiring mutex - solves deadlocks when we
1240 * re-enter the quota code and are already holding the mutex */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241 if (IS_NOQUOTA(inode)) {
1242out_sub:
1243 inode_sub_bytes(inode, number);
1244 return QUOTA_OK;
1245 }
1246 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1247 /* Now recheck reliably when holding dqptr_sem */
1248 if (IS_NOQUOTA(inode)) {
1249 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1250 goto out_sub;
1251 }
1252 spin_lock(&dq_data_lock);
1253 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1254 if (inode->i_dquot[cnt] == NODQUOT)
1255 continue;
1256 dquot_decr_space(inode->i_dquot[cnt], number);
1257 }
1258 inode_sub_bytes(inode, number);
1259 spin_unlock(&dq_data_lock);
1260 /* Dirtify all the dquots - this can block when journalling */
1261 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1262 if (inode->i_dquot[cnt])
1263 mark_dquot_dirty(inode->i_dquot[cnt]);
1264 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1265 return QUOTA_OK;
1266}
1267
1268/*
1269 * This operation can block, but only after everything is updated
1270 */
1271int dquot_free_inode(const struct inode *inode, unsigned long number)
1272{
1273 unsigned int cnt;
1274
Ingo Molnard3be9152006-03-23 03:00:29 -08001275 /* First test before acquiring mutex - solves deadlocks when we
1276 * re-enter the quota code and are already holding the mutex */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277 if (IS_NOQUOTA(inode))
1278 return QUOTA_OK;
1279 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1280 /* Now recheck reliably when holding dqptr_sem */
1281 if (IS_NOQUOTA(inode)) {
1282 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1283 return QUOTA_OK;
1284 }
1285 spin_lock(&dq_data_lock);
1286 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1287 if (inode->i_dquot[cnt] == NODQUOT)
1288 continue;
1289 dquot_decr_inodes(inode->i_dquot[cnt], number);
1290 }
1291 spin_unlock(&dq_data_lock);
1292 /* Dirtify all the dquots - this can block when journalling */
1293 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1294 if (inode->i_dquot[cnt])
1295 mark_dquot_dirty(inode->i_dquot[cnt]);
1296 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1297 return QUOTA_OK;
1298}
1299
1300/*
1301 * Transfer the number of inode and blocks from one diskquota to an other.
1302 *
1303 * This operation can block, but only after everything is updated
1304 * A transaction must be started when entering this function.
1305 */
1306int dquot_transfer(struct inode *inode, struct iattr *iattr)
1307{
1308 qsize_t space;
1309 struct dquot *transfer_from[MAXQUOTAS];
1310 struct dquot *transfer_to[MAXQUOTAS];
1311 int cnt, ret = NO_QUOTA, chuid = (iattr->ia_valid & ATTR_UID) && inode->i_uid != iattr->ia_uid,
1312 chgid = (iattr->ia_valid & ATTR_GID) && inode->i_gid != iattr->ia_gid;
1313 char warntype[MAXQUOTAS];
1314
Ingo Molnard3be9152006-03-23 03:00:29 -08001315 /* First test before acquiring mutex - solves deadlocks when we
1316 * re-enter the quota code and are already holding the mutex */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001317 if (IS_NOQUOTA(inode))
1318 return QUOTA_OK;
1319 /* Clear the arrays */
1320 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1321 transfer_to[cnt] = transfer_from[cnt] = NODQUOT;
Jan Kara8e893462007-10-16 23:29:31 -07001322 warntype[cnt] = QUOTA_NL_NOWARN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 }
1324 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1325 /* Now recheck reliably when holding dqptr_sem */
1326 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
1327 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1328 return QUOTA_OK;
1329 }
1330 /* First build the transfer_to list - here we can block on
1331 * reading/instantiating of dquots. We know that the transaction for
1332 * us was already started so we don't violate lock ranking here */
1333 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1334 switch (cnt) {
1335 case USRQUOTA:
1336 if (!chuid)
1337 continue;
1338 transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_uid, cnt);
1339 break;
1340 case GRPQUOTA:
1341 if (!chgid)
1342 continue;
1343 transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_gid, cnt);
1344 break;
1345 }
1346 }
1347 spin_lock(&dq_data_lock);
1348 space = inode_get_bytes(inode);
1349 /* Build the transfer_from list and check the limits */
1350 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1351 if (transfer_to[cnt] == NODQUOT)
1352 continue;
1353 transfer_from[cnt] = inode->i_dquot[cnt];
1354 if (check_idq(transfer_to[cnt], 1, warntype+cnt) == NO_QUOTA ||
1355 check_bdq(transfer_to[cnt], space, 0, warntype+cnt) == NO_QUOTA)
1356 goto warn_put_all;
1357 }
1358
1359 /*
1360 * Finally perform the needed transfer from transfer_from to transfer_to
1361 */
1362 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1363 /*
1364 * Skip changes for same uid or gid or for turned off quota-type.
1365 */
1366 if (transfer_to[cnt] == NODQUOT)
1367 continue;
1368
1369 /* Due to IO error we might not have transfer_from[] structure */
1370 if (transfer_from[cnt]) {
1371 dquot_decr_inodes(transfer_from[cnt], 1);
1372 dquot_decr_space(transfer_from[cnt], space);
1373 }
1374
1375 dquot_incr_inodes(transfer_to[cnt], 1);
1376 dquot_incr_space(transfer_to[cnt], space);
1377
1378 inode->i_dquot[cnt] = transfer_to[cnt];
1379 }
1380 ret = QUOTA_OK;
1381warn_put_all:
1382 spin_unlock(&dq_data_lock);
1383 /* Dirtify all the dquots - this can block when journalling */
1384 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1385 if (transfer_from[cnt])
1386 mark_dquot_dirty(transfer_from[cnt]);
1387 if (transfer_to[cnt])
1388 mark_dquot_dirty(transfer_to[cnt]);
1389 }
1390 flush_warnings(transfer_to, warntype);
1391
1392 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1393 if (ret == QUOTA_OK && transfer_from[cnt] != NODQUOT)
1394 dqput(transfer_from[cnt]);
1395 if (ret == NO_QUOTA && transfer_to[cnt] != NODQUOT)
1396 dqput(transfer_to[cnt]);
1397 }
1398 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1399 return ret;
1400}
1401
1402/*
1403 * Write info of quota file to disk
1404 */
1405int dquot_commit_info(struct super_block *sb, int type)
1406{
1407 int ret;
1408 struct quota_info *dqopt = sb_dqopt(sb);
1409
Ingo Molnard3be9152006-03-23 03:00:29 -08001410 mutex_lock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001411 ret = dqopt->ops[type]->write_file_info(sb, type);
Ingo Molnard3be9152006-03-23 03:00:29 -08001412 mutex_unlock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413 return ret;
1414}
1415
1416/*
1417 * Definitions of diskquota operations.
1418 */
1419struct dquot_operations dquot_operations = {
1420 .initialize = dquot_initialize,
1421 .drop = dquot_drop,
1422 .alloc_space = dquot_alloc_space,
1423 .alloc_inode = dquot_alloc_inode,
1424 .free_space = dquot_free_space,
1425 .free_inode = dquot_free_inode,
1426 .transfer = dquot_transfer,
1427 .write_dquot = dquot_commit,
1428 .acquire_dquot = dquot_acquire,
1429 .release_dquot = dquot_release,
1430 .mark_dirty = dquot_mark_dquot_dirty,
1431 .write_info = dquot_commit_info
1432};
1433
1434static inline void set_enable_flags(struct quota_info *dqopt, int type)
1435{
1436 switch (type) {
1437 case USRQUOTA:
1438 dqopt->flags |= DQUOT_USR_ENABLED;
1439 break;
1440 case GRPQUOTA:
1441 dqopt->flags |= DQUOT_GRP_ENABLED;
1442 break;
1443 }
1444}
1445
1446static inline void reset_enable_flags(struct quota_info *dqopt, int type)
1447{
1448 switch (type) {
1449 case USRQUOTA:
1450 dqopt->flags &= ~DQUOT_USR_ENABLED;
1451 break;
1452 case GRPQUOTA:
1453 dqopt->flags &= ~DQUOT_GRP_ENABLED;
1454 break;
1455 }
1456}
1457
1458/*
1459 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
1460 */
1461int vfs_quota_off(struct super_block *sb, int type)
1462{
1463 int cnt;
1464 struct quota_info *dqopt = sb_dqopt(sb);
1465 struct inode *toputinode[MAXQUOTAS];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001466
1467 /* We need to serialize quota_off() for device */
Ingo Molnard3be9152006-03-23 03:00:29 -08001468 mutex_lock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001469 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1470 toputinode[cnt] = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001471 if (type != -1 && cnt != type)
1472 continue;
1473 if (!sb_has_quota_enabled(sb, cnt))
1474 continue;
1475 reset_enable_flags(dqopt, cnt);
1476
1477 /* Note: these are blocking operations */
1478 drop_dquot_ref(sb, cnt);
1479 invalidate_dquots(sb, cnt);
1480 /*
1481 * Now all dquots should be invalidated, all writes done so we should be only
1482 * users of the info. No locks needed.
1483 */
1484 if (info_dirty(&dqopt->info[cnt]))
1485 sb->dq_op->write_info(sb, cnt);
1486 if (dqopt->ops[cnt]->free_file_info)
1487 dqopt->ops[cnt]->free_file_info(sb, cnt);
1488 put_quota_format(dqopt->info[cnt].dqi_format);
1489
1490 toputinode[cnt] = dqopt->files[cnt];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491 dqopt->files[cnt] = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492 dqopt->info[cnt].dqi_flags = 0;
1493 dqopt->info[cnt].dqi_igrace = 0;
1494 dqopt->info[cnt].dqi_bgrace = 0;
1495 dqopt->ops[cnt] = NULL;
1496 }
Ingo Molnard3be9152006-03-23 03:00:29 -08001497 mutex_unlock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498 /* Sync the superblock so that buffers with quota data are written to
Al Viro7b7b1ac2005-11-07 17:13:39 -05001499 * disk (and so userspace sees correct data afterwards). */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001500 if (sb->s_op->sync_fs)
1501 sb->s_op->sync_fs(sb, 1);
1502 sync_blockdev(sb->s_bdev);
1503 /* Now the quota files are just ordinary files and we can set the
1504 * inode flags back. Moreover we discard the pagecache so that
1505 * userspace sees the writes we did bypassing the pagecache. We
1506 * must also discard the blockdev buffers so that we see the
1507 * changes done by userspace on the next quotaon() */
1508 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1509 if (toputinode[cnt]) {
Ingo Molnard3be9152006-03-23 03:00:29 -08001510 mutex_lock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001511 /* If quota was reenabled in the meantime, we have
1512 * nothing to do */
1513 if (!sb_has_quota_enabled(sb, cnt)) {
Jan Kara79254092007-05-16 22:11:19 -07001514 mutex_lock_nested(&toputinode[cnt]->i_mutex, I_MUTEX_QUOTA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001515 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE |
1516 S_NOATIME | S_NOQUOTA);
1517 truncate_inode_pages(&toputinode[cnt]->i_data, 0);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -08001518 mutex_unlock(&toputinode[cnt]->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001519 mark_inode_dirty(toputinode[cnt]);
1520 iput(toputinode[cnt]);
1521 }
Ingo Molnard3be9152006-03-23 03:00:29 -08001522 mutex_unlock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001523 }
1524 if (sb->s_bdev)
Peter Zijlstraf98393a2007-05-06 14:49:54 -07001525 invalidate_bdev(sb->s_bdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001526 return 0;
1527}
1528
1529/*
1530 * Turn quotas on on a device
1531 */
1532
1533/* Helper function when we already have the inode */
1534static int vfs_quota_on_inode(struct inode *inode, int type, int format_id)
1535{
1536 struct quota_format_type *fmt = find_quota_format(format_id);
1537 struct super_block *sb = inode->i_sb;
1538 struct quota_info *dqopt = sb_dqopt(sb);
1539 int error;
1540 int oldflags = -1;
1541
1542 if (!fmt)
1543 return -ESRCH;
1544 if (!S_ISREG(inode->i_mode)) {
1545 error = -EACCES;
1546 goto out_fmt;
1547 }
1548 if (IS_RDONLY(inode)) {
1549 error = -EROFS;
1550 goto out_fmt;
1551 }
1552 if (!sb->s_op->quota_write || !sb->s_op->quota_read) {
1553 error = -EINVAL;
1554 goto out_fmt;
1555 }
1556
1557 /* As we bypass the pagecache we must now flush the inode so that
1558 * we see all the changes from userspace... */
1559 write_inode_now(inode, 1);
1560 /* And now flush the block cache so that kernel sees the changes */
Peter Zijlstraf98393a2007-05-06 14:49:54 -07001561 invalidate_bdev(sb->s_bdev);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -08001562 mutex_lock(&inode->i_mutex);
Ingo Molnard3be9152006-03-23 03:00:29 -08001563 mutex_lock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001564 if (sb_has_quota_enabled(sb, type)) {
1565 error = -EBUSY;
1566 goto out_lock;
1567 }
1568 /* We don't want quota and atime on quota files (deadlocks possible)
1569 * Also nobody should write to the file - we use special IO operations
1570 * which ignore the immutable bit. */
1571 down_write(&dqopt->dqptr_sem);
1572 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | S_NOQUOTA);
1573 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE;
1574 up_write(&dqopt->dqptr_sem);
Jan Kara31e7ad62005-04-16 15:25:46 -07001575 sb->dq_op->drop(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001576
1577 error = -EIO;
1578 dqopt->files[type] = igrab(inode);
1579 if (!dqopt->files[type])
1580 goto out_lock;
1581 error = -EINVAL;
1582 if (!fmt->qf_ops->check_quota_file(sb, type))
1583 goto out_file_init;
1584
1585 dqopt->ops[type] = fmt->qf_ops;
1586 dqopt->info[type].dqi_format = fmt;
1587 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
Ingo Molnard3be9152006-03-23 03:00:29 -08001588 mutex_lock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001589 if ((error = dqopt->ops[type]->read_file_info(sb, type)) < 0) {
Ingo Molnard3be9152006-03-23 03:00:29 -08001590 mutex_unlock(&dqopt->dqio_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001591 goto out_file_init;
1592 }
Ingo Molnard3be9152006-03-23 03:00:29 -08001593 mutex_unlock(&dqopt->dqio_mutex);
Jes Sorensen1b1dcc12006-01-09 15:59:24 -08001594 mutex_unlock(&inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001595 set_enable_flags(dqopt, type);
1596
1597 add_dquot_ref(sb, type);
Ingo Molnard3be9152006-03-23 03:00:29 -08001598 mutex_unlock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001599
1600 return 0;
1601
1602out_file_init:
1603 dqopt->files[type] = NULL;
1604 iput(inode);
1605out_lock:
Ingo Molnard3be9152006-03-23 03:00:29 -08001606 mutex_unlock(&dqopt->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001607 if (oldflags != -1) {
1608 down_write(&dqopt->dqptr_sem);
1609 /* Set the flags back (in the case of accidental quotaon()
1610 * on a wrong file we don't want to mess up the flags) */
1611 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE);
1612 inode->i_flags |= oldflags;
1613 up_write(&dqopt->dqptr_sem);
1614 }
Jes Sorensen1b1dcc12006-01-09 15:59:24 -08001615 mutex_unlock(&inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001616out_fmt:
1617 put_quota_format(fmt);
1618
1619 return error;
1620}
1621
1622/* Actual function called from quotactl() */
1623int vfs_quota_on(struct super_block *sb, int type, int format_id, char *path)
1624{
1625 struct nameidata nd;
1626 int error;
1627
1628 error = path_lookup(path, LOOKUP_FOLLOW, &nd);
1629 if (error < 0)
1630 return error;
1631 error = security_quota_on(nd.dentry);
1632 if (error)
1633 goto out_path;
1634 /* Quota file not on the same filesystem? */
1635 if (nd.mnt->mnt_sb != sb)
1636 error = -EXDEV;
Al Viro7b7b1ac2005-11-07 17:13:39 -05001637 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638 error = vfs_quota_on_inode(nd.dentry->d_inode, type, format_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001639out_path:
1640 path_release(&nd);
1641 return error;
1642}
1643
1644/*
1645 * This function is used when filesystem needs to initialize quotas
1646 * during mount time.
1647 */
Christoph Hellwig84de8562005-06-23 00:09:16 -07001648int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
1649 int format_id, int type)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001650{
Christoph Hellwig84de8562005-06-23 00:09:16 -07001651 struct dentry *dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001652 int error;
1653
Christoph Hellwig2fa389c2005-06-23 00:09:16 -07001654 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name));
Christoph Hellwig84de8562005-06-23 00:09:16 -07001655 if (IS_ERR(dentry))
1656 return PTR_ERR(dentry);
1657
Jan Kara154f4842005-11-28 13:44:14 -08001658 if (!dentry->d_inode) {
1659 error = -ENOENT;
1660 goto out;
1661 }
1662
Linus Torvalds1da177e2005-04-16 15:20:36 -07001663 error = security_quota_on(dentry);
Christoph Hellwig84de8562005-06-23 00:09:16 -07001664 if (!error)
1665 error = vfs_quota_on_inode(dentry->d_inode, type, format_id);
1666
Jan Kara154f4842005-11-28 13:44:14 -08001667out:
Christoph Hellwig84de8562005-06-23 00:09:16 -07001668 dput(dentry);
1669 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670}
1671
1672/* Generic routine for getting common part of quota structure */
1673static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
1674{
1675 struct mem_dqblk *dm = &dquot->dq_dqb;
1676
1677 spin_lock(&dq_data_lock);
1678 di->dqb_bhardlimit = dm->dqb_bhardlimit;
1679 di->dqb_bsoftlimit = dm->dqb_bsoftlimit;
1680 di->dqb_curspace = dm->dqb_curspace;
1681 di->dqb_ihardlimit = dm->dqb_ihardlimit;
1682 di->dqb_isoftlimit = dm->dqb_isoftlimit;
1683 di->dqb_curinodes = dm->dqb_curinodes;
1684 di->dqb_btime = dm->dqb_btime;
1685 di->dqb_itime = dm->dqb_itime;
1686 di->dqb_valid = QIF_ALL;
1687 spin_unlock(&dq_data_lock);
1688}
1689
1690int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
1691{
1692 struct dquot *dquot;
1693
Ingo Molnard3be9152006-03-23 03:00:29 -08001694 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001695 if (!(dquot = dqget(sb, id, type))) {
Ingo Molnard3be9152006-03-23 03:00:29 -08001696 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001697 return -ESRCH;
1698 }
1699 do_get_dqblk(dquot, di);
1700 dqput(dquot);
Ingo Molnard3be9152006-03-23 03:00:29 -08001701 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001702 return 0;
1703}
1704
1705/* Generic routine for setting common part of quota structure */
1706static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
1707{
1708 struct mem_dqblk *dm = &dquot->dq_dqb;
1709 int check_blim = 0, check_ilim = 0;
1710
1711 spin_lock(&dq_data_lock);
1712 if (di->dqb_valid & QIF_SPACE) {
1713 dm->dqb_curspace = di->dqb_curspace;
1714 check_blim = 1;
1715 }
1716 if (di->dqb_valid & QIF_BLIMITS) {
1717 dm->dqb_bsoftlimit = di->dqb_bsoftlimit;
1718 dm->dqb_bhardlimit = di->dqb_bhardlimit;
1719 check_blim = 1;
1720 }
1721 if (di->dqb_valid & QIF_INODES) {
1722 dm->dqb_curinodes = di->dqb_curinodes;
1723 check_ilim = 1;
1724 }
1725 if (di->dqb_valid & QIF_ILIMITS) {
1726 dm->dqb_isoftlimit = di->dqb_isoftlimit;
1727 dm->dqb_ihardlimit = di->dqb_ihardlimit;
1728 check_ilim = 1;
1729 }
1730 if (di->dqb_valid & QIF_BTIME)
1731 dm->dqb_btime = di->dqb_btime;
1732 if (di->dqb_valid & QIF_ITIME)
1733 dm->dqb_itime = di->dqb_itime;
1734
1735 if (check_blim) {
1736 if (!dm->dqb_bsoftlimit || toqb(dm->dqb_curspace) < dm->dqb_bsoftlimit) {
1737 dm->dqb_btime = 0;
1738 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
1739 }
1740 else if (!(di->dqb_valid & QIF_BTIME)) /* Set grace only if user hasn't provided his own... */
1741 dm->dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace;
1742 }
1743 if (check_ilim) {
1744 if (!dm->dqb_isoftlimit || dm->dqb_curinodes < dm->dqb_isoftlimit) {
1745 dm->dqb_itime = 0;
1746 clear_bit(DQ_INODES_B, &dquot->dq_flags);
1747 }
1748 else if (!(di->dqb_valid & QIF_ITIME)) /* Set grace only if user hasn't provided his own... */
1749 dm->dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
1750 }
1751 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || dm->dqb_isoftlimit)
1752 clear_bit(DQ_FAKE_B, &dquot->dq_flags);
1753 else
1754 set_bit(DQ_FAKE_B, &dquot->dq_flags);
1755 spin_unlock(&dq_data_lock);
1756 mark_dquot_dirty(dquot);
1757}
1758
1759int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
1760{
1761 struct dquot *dquot;
1762
Ingo Molnard3be9152006-03-23 03:00:29 -08001763 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001764 if (!(dquot = dqget(sb, id, type))) {
Ingo Molnard3be9152006-03-23 03:00:29 -08001765 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001766 return -ESRCH;
1767 }
1768 do_set_dqblk(dquot, di);
1769 dqput(dquot);
Ingo Molnard3be9152006-03-23 03:00:29 -08001770 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001771 return 0;
1772}
1773
1774/* Generic routine for getting common part of quota file information */
1775int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
1776{
1777 struct mem_dqinfo *mi;
1778
Ingo Molnard3be9152006-03-23 03:00:29 -08001779 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001780 if (!sb_has_quota_enabled(sb, type)) {
Ingo Molnard3be9152006-03-23 03:00:29 -08001781 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001782 return -ESRCH;
1783 }
1784 mi = sb_dqopt(sb)->info + type;
1785 spin_lock(&dq_data_lock);
1786 ii->dqi_bgrace = mi->dqi_bgrace;
1787 ii->dqi_igrace = mi->dqi_igrace;
1788 ii->dqi_flags = mi->dqi_flags & DQF_MASK;
1789 ii->dqi_valid = IIF_ALL;
1790 spin_unlock(&dq_data_lock);
Ingo Molnard3be9152006-03-23 03:00:29 -08001791 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001792 return 0;
1793}
1794
1795/* Generic routine for setting common part of quota file information */
1796int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
1797{
1798 struct mem_dqinfo *mi;
1799
Ingo Molnard3be9152006-03-23 03:00:29 -08001800 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001801 if (!sb_has_quota_enabled(sb, type)) {
Ingo Molnard3be9152006-03-23 03:00:29 -08001802 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001803 return -ESRCH;
1804 }
1805 mi = sb_dqopt(sb)->info + type;
1806 spin_lock(&dq_data_lock);
1807 if (ii->dqi_valid & IIF_BGRACE)
1808 mi->dqi_bgrace = ii->dqi_bgrace;
1809 if (ii->dqi_valid & IIF_IGRACE)
1810 mi->dqi_igrace = ii->dqi_igrace;
1811 if (ii->dqi_valid & IIF_FLAGS)
1812 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | (ii->dqi_flags & DQF_MASK);
1813 spin_unlock(&dq_data_lock);
1814 mark_info_dirty(sb, type);
1815 /* Force write to disk */
1816 sb->dq_op->write_info(sb, type);
Ingo Molnard3be9152006-03-23 03:00:29 -08001817 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001818 return 0;
1819}
1820
1821struct quotactl_ops vfs_quotactl_ops = {
1822 .quota_on = vfs_quota_on,
1823 .quota_off = vfs_quota_off,
1824 .quota_sync = vfs_quota_sync,
1825 .get_info = vfs_get_dqinfo,
1826 .set_info = vfs_set_dqinfo,
1827 .get_dqblk = vfs_get_dqblk,
1828 .set_dqblk = vfs_set_dqblk
1829};
1830
1831static ctl_table fs_dqstats_table[] = {
1832 {
1833 .ctl_name = FS_DQ_LOOKUPS,
1834 .procname = "lookups",
1835 .data = &dqstats.lookups,
1836 .maxlen = sizeof(int),
1837 .mode = 0444,
1838 .proc_handler = &proc_dointvec,
1839 },
1840 {
1841 .ctl_name = FS_DQ_DROPS,
1842 .procname = "drops",
1843 .data = &dqstats.drops,
1844 .maxlen = sizeof(int),
1845 .mode = 0444,
1846 .proc_handler = &proc_dointvec,
1847 },
1848 {
1849 .ctl_name = FS_DQ_READS,
1850 .procname = "reads",
1851 .data = &dqstats.reads,
1852 .maxlen = sizeof(int),
1853 .mode = 0444,
1854 .proc_handler = &proc_dointvec,
1855 },
1856 {
1857 .ctl_name = FS_DQ_WRITES,
1858 .procname = "writes",
1859 .data = &dqstats.writes,
1860 .maxlen = sizeof(int),
1861 .mode = 0444,
1862 .proc_handler = &proc_dointvec,
1863 },
1864 {
1865 .ctl_name = FS_DQ_CACHE_HITS,
1866 .procname = "cache_hits",
1867 .data = &dqstats.cache_hits,
1868 .maxlen = sizeof(int),
1869 .mode = 0444,
1870 .proc_handler = &proc_dointvec,
1871 },
1872 {
1873 .ctl_name = FS_DQ_ALLOCATED,
1874 .procname = "allocated_dquots",
1875 .data = &dqstats.allocated_dquots,
1876 .maxlen = sizeof(int),
1877 .mode = 0444,
1878 .proc_handler = &proc_dointvec,
1879 },
1880 {
1881 .ctl_name = FS_DQ_FREE,
1882 .procname = "free_dquots",
1883 .data = &dqstats.free_dquots,
1884 .maxlen = sizeof(int),
1885 .mode = 0444,
1886 .proc_handler = &proc_dointvec,
1887 },
1888 {
1889 .ctl_name = FS_DQ_SYNCS,
1890 .procname = "syncs",
1891 .data = &dqstats.syncs,
1892 .maxlen = sizeof(int),
1893 .mode = 0444,
1894 .proc_handler = &proc_dointvec,
1895 },
Jan Kara8e893462007-10-16 23:29:31 -07001896#ifdef CONFIG_PRINT_QUOTA_WARNING
Linus Torvalds1da177e2005-04-16 15:20:36 -07001897 {
1898 .ctl_name = FS_DQ_WARNINGS,
1899 .procname = "warnings",
1900 .data = &flag_print_warnings,
1901 .maxlen = sizeof(int),
1902 .mode = 0644,
1903 .proc_handler = &proc_dointvec,
1904 },
Jan Kara8e893462007-10-16 23:29:31 -07001905#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001906 { .ctl_name = 0 },
1907};
1908
1909static ctl_table fs_table[] = {
1910 {
1911 .ctl_name = FS_DQSTATS,
1912 .procname = "quota",
1913 .mode = 0555,
1914 .child = fs_dqstats_table,
1915 },
1916 { .ctl_name = 0 },
1917};
1918
1919static ctl_table sys_table[] = {
1920 {
1921 .ctl_name = CTL_FS,
1922 .procname = "fs",
1923 .mode = 0555,
1924 .child = fs_table,
1925 },
1926 { .ctl_name = 0 },
1927};
1928
1929static int __init dquot_init(void)
1930{
1931 int i;
1932 unsigned long nr_hash, order;
1933
1934 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
1935
Eric W. Biederman0b4d4142007-02-14 00:34:09 -08001936 register_sysctl_table(sys_table);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001937
Paul Mundt20c2df82007-07-20 10:11:58 +09001938 dquot_cachep = kmem_cache_create("dquot",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001939 sizeof(struct dquot), sizeof(unsigned long) * 4,
Paul Jacksonfffb60f2006-03-24 03:16:06 -08001940 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
1941 SLAB_MEM_SPREAD|SLAB_PANIC),
Paul Mundt20c2df82007-07-20 10:11:58 +09001942 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001943
1944 order = 0;
1945 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order);
1946 if (!dquot_hash)
1947 panic("Cannot create dquot hash table");
1948
1949 /* Find power-of-two hlist_heads which can fit into allocation */
1950 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
1951 dq_hash_bits = 0;
1952 do {
1953 dq_hash_bits++;
1954 } while (nr_hash >> dq_hash_bits);
1955 dq_hash_bits--;
1956
1957 nr_hash = 1UL << dq_hash_bits;
1958 dq_hash_mask = nr_hash - 1;
1959 for (i = 0; i < nr_hash; i++)
1960 INIT_HLIST_HEAD(dquot_hash + i);
1961
1962 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n",
1963 nr_hash, order, (PAGE_SIZE << order));
1964
Rusty Russell8e1f9362007-07-17 04:03:17 -07001965 register_shrinker(&dqcache_shrinker);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001966
Jan Kara8e893462007-10-16 23:29:31 -07001967#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
1968 if (genl_register_family(&quota_genl_family) != 0)
1969 printk(KERN_ERR "VFS: Failed to create quota netlink interface.\n");
1970#endif
1971
Linus Torvalds1da177e2005-04-16 15:20:36 -07001972 return 0;
1973}
1974module_init(dquot_init);
1975
1976EXPORT_SYMBOL(register_quota_format);
1977EXPORT_SYMBOL(unregister_quota_format);
1978EXPORT_SYMBOL(dqstats);
1979EXPORT_SYMBOL(dq_data_lock);
1980EXPORT_SYMBOL(vfs_quota_on);
1981EXPORT_SYMBOL(vfs_quota_on_mount);
1982EXPORT_SYMBOL(vfs_quota_off);
1983EXPORT_SYMBOL(vfs_quota_sync);
1984EXPORT_SYMBOL(vfs_get_dqinfo);
1985EXPORT_SYMBOL(vfs_set_dqinfo);
1986EXPORT_SYMBOL(vfs_get_dqblk);
1987EXPORT_SYMBOL(vfs_set_dqblk);
1988EXPORT_SYMBOL(dquot_commit);
1989EXPORT_SYMBOL(dquot_commit_info);
1990EXPORT_SYMBOL(dquot_acquire);
1991EXPORT_SYMBOL(dquot_release);
1992EXPORT_SYMBOL(dquot_mark_dquot_dirty);
1993EXPORT_SYMBOL(dquot_initialize);
1994EXPORT_SYMBOL(dquot_drop);
1995EXPORT_SYMBOL(dquot_alloc_space);
1996EXPORT_SYMBOL(dquot_alloc_inode);
1997EXPORT_SYMBOL(dquot_free_space);
1998EXPORT_SYMBOL(dquot_free_inode);
1999EXPORT_SYMBOL(dquot_transfer);